A solid state drive (“SSD”) is a memory device capable of retaining data persistently without connecting to a power supply. The SSD uses various non-volatile memory devices such as NAND based flash memory or phase change memory to store data or digital information. With rapidly increasing storage capacity as well as access speed associated with non-volatile memory, SSD becomes more popular for storing non-volatile data in computing systems, such as laptop computers, desktop computers, mobile devices, tablets, servers, routers, network devices, and the like.
A conventional flash based SSD is organized and configured to replace or substitute traditional hard disk drive (“HDD”) and use similar input and output (“I/O”) access interface as traditional non-volatile storage drives. For example, HDD typically employs various types of I/O access interface, such as serial attached small computer system interface (“SAS”), serial ATA (“SATA”) interface, to handle logical block address (“LBA”) based storage access. Each block or sector of LBA, for example, can be configurable to have a storage capacity of 512 bytes.
To use similar HDD I/O access interface, conventional flash based SSD can be configured to have a block size of 4096 bytes or 4 kilobyte (“Kbyte”) block. The flash memory typically has a minimum unit such as a block size for a read-or-write operation at a given time. In general, the speed for flash based SSD is typically faster than HDD.